Intramolecular aldol condensation of Michael adducts of levoglucosenone and cyclododecanone

Base-promoted intramolecular aldol condensation of diastereomeric Michael adducts of levoglucosenone and cyclododecanone affords 12-hydroxy-14,20-dioxatetra-cyclo[9.6.1.1^12,17.1^13,16]icosan-18-one as a mixture of three diastereomers. The products thus obtained are promising for synthesizing 14-membered macrocyclic compounds, including cembranoids and their analogues.